Clutch.



0.5 SCHNUCK CLUTCH.

APPLICATION FI LED DEC-29, 1914.

1,11%;589] Patented May 9,1916.-

2 SHEETS-SHEET 2- 11741? I g! 2, y/NL'ENTOA.

UNITED sTA ES .rAi NToFFICE- can; in"sonnucx orzaiisoivm, coNNEoTIouT, ASSIGNOR To FARREL Foui mw & MACHINE company, or AnsoNIA, CONNECTICUT, A CORPO RATION or GON- NEGTICUT.

Toall whom itmay concern:

Be it known that I, CARL F-f'SoiiNUcK, 'a'citizen of the United States, residing at Ansonia, in the county of New Haven and State of Connecticut, have invented certain new and useful'Improvements in Clutches, of which thefollowing is a full, clear, and exact description.

This invention relates'to clutches,- and more particularly to coil orstrap clutcheswhich a'rei operated eleotromagnetically.

Clutches of this type are commonly used for connecting electric and other prime mov- 'ers to rubber-mills,.rolling mills, crushing and stamping machinery, and the like. 'In the operation of the clutch, the driving part and the driven part are coupled together by means of a steel or other coil, which is fixed relative to one ofsaid parts, and arranged to be engaged and released relative to the other part by means of a suitable electromagnet.

Heretofore it has been proposed to construct a clutch wherein one of the members,

for instance the driving member, carries a coil which is adapted to be frictionally engaged with the other (driven) member, by means of an electromagnet which looks the 'free end or tail of the coil to the driven member and thereby retards such free end or'tail. Thus 1 sufficient torsion is exerted upon the coil to cause it to frictionally engage. the driven or engagement with a art'of-the magnet.

member anddrive, the same. The electromagnet has been directly carried by the.

driven member proper, and a special disklike armature, or engaging member, has been keyed to one end of the friction coil to cooperate with the magnet. In this construetion the armature .or engaging member is held out of engagement with the magnet, whenfthe clutch is'disengaged, by special means which are embodied in the clutch construction for that purpose, but when the clutch is to be engaged, said; armature or engaging member is moved into full contact One of the primary 0 jectsfof my invention is to furnish a clutch in which a special engaging member or armature is dispensed with, and wherein a part of the friction coil is adapted .to act as an armature, while nevertheless, itretains at least to a certain degree, its normal function of frictionally Specification of Letters Patent.

' vention, the

relates. a

CLUTCH;

engaging the driven member to assist in driving the same. By this change, the construction of the clutch is'considerably simfplified'and improved. In certain aspects of I -'the invention, however, this is not a mate rial feature.

I Another object which I have in view is to furnish a clutch in which no special -means are necessary for holding the armature out of contact with the magnet when the clutch is disengaged, and in" which the armature may retain substantially the same positionaxially of the magnet, when'lthe clutch is disengaged, that it occupies when the clutch is engage Another improvement which I have in view is the provision of means for preventing the looking or gripping together of the armature and magnet by residual magnetism when the current has been cut ofl" This is an objection of some moment which exists,

for example, where there is steel tosteel con-'" tact between the magnet and armaturelin the driving position, because in this-case it is ojg'ten'difiicult or impossibleto disengage the eliitch parts, .I overcome this disad'van- Patented-1liay 9, 1916. Application filed December29, 1914. Seria1'No. 878,494.

erably be constituted by a strip of brass, or

other non-magnetic material, permanently interposed between the armature and'the magnet, but in the'broad aspects of the inmaterial.

I also have in view the general improvement of the construction and operation of devices of 'the class to which my invention To these and particular construction is im-- other ends, the invention consists in the novel features and combinations of part's to be hereinafter described and claimed. c

In the accompanying, drawings, .Figure 1 is a somewhat diagrammatic longitudinal section of a clutch gembodying my improvements, taken on line 1 1 of Fig.2; Fig. 2

is an end elevation of the clutch, with certain parts brokenaway gand Fig.3 isca plan 2 view of one end portion of the clutch, with the casing shown in section.

- I have shown my improvements applied to a clutch for coupling a continuously rotating gear wheel or pulley to a driven shaft 21, .but this is not an essential feature.

.I have also shown my improvements as applied to a clutch whereinthe continuously rotating member carries a helical friction coil 22,- which rotates therewith, and is.

adapted to be brought into frictional contact with a drum or chill 2 3 fixed to the ;dr1ven member 21, and surrounding the drum, bywinding' up the coil; but this is likewise an unessentialfeature inmost as pects ofmy. inventlon', because, of course",

an obvious reversal of. the several parts would be within thescope of the invention. The drum or chill23 is. fixed nonrotatively to the driven shaft'21, by meansof a key or feather24. Surrounding the drum and bearing thereon is adriving plate 25, to.

which one end of the coil 22 is. fixed. The' driving plate 25 is, in this instance, formed as an integralpart of the gear wheel or pulley '20, but this is not essential. The coil 22 is so arranged as tosurround' that portion of thedrum which is not-surrounded by the driving plate. Whenthe parts are in the disengaged position. (Fig. 1), the coil moves about the drum with a certain amountgof clearance.

so-called head, which is indicated generally I at 26-, is interlocked with the driving plate in any appropriate manner. By preference,

the head of the coil carries a lug'which fits into a notch of the driving plate, but asgthis means of connection is well-known in the art, I have not considered it necessary to end of the drum 23 by bolts 30 passing illustrate it in detail. The opposite end or tail of the coil is'indicated at 27 in Fig. 2,

and the last convolution at the free end portion of the coil, which is indicated at 28,

is adapted toact as an armature of an electromagnet 29 attached to or forming part of the driven member 23. In the form shown, the magnet 29 is formed of a ring or annulus of soft dynamosteel bolted to the through lugs 31 on'the ring. On the inner face of the ring, whichis of greater diameter than the drum,'and extends beyond the same, the ring is provided with a groove in which is fitted a ring-like magnet coil 32. The inner diameter of the magnet-coil is preferably somewhat greater than the inner diameter of the end convolution 2815f the coil, where- I as the outer diameter of ,the magnet coil is of said end convolution.

preferably smaller than the outer diameter The magnet formed by the magnet plate 29 and coil 32 is located opposite the end convolution 28,

That part of the-friction coil 22 which is connected to the driving plate 25 is called the head. of the coil, and this so that when themagnet is energized, it will exert -an even-pull on the end convolution 28 in a'direction axially of the friction .coil. Means are provided, however, for preventlng contact of the end convolution or winding 28 with the magnet proper. In the ex ample shown, an annul'ar'plate 33 of brass,

or other'non-magnetic material,- is interposed between the magnet and the'coi-l, and I prefer'to attach this brass plate to the magnetby means such as screws 34, although in some cases, said, plate, or its equivalent, might be attached tothe armaturemember rather than to the magnet member. In theform shown, this non-magnetic plate covers the whole portion of themagnet which is adjacent to the end convolution of the friction coil, and as it prevents contactof the endconvolution'28 with any part of the magnet proper, it serves toeliminate any tendency of the .magnet and armature to cling together byresidual magnetismwhen the current is cut off; I

Insulated cOnducting Wires 35, 36 pass from the terminals of the magnet coil 32,

through suitable openings 37, 38 in the magnet plate 29, and are connected with binding posts 39, 40;. These'binding posts are mounted on small plates 41, 42' of insulating material screwed to the magnet plate 29. From the binding posts 39, 40insulate-d conducting wires 43, 44 pass into the vspacewithin the drum 23, preferably through suitable grooves or conduits 4:5, etfi, which may be conveniently formed at 'theinner surface of the drum. The conducting wire43 is connected with an insulated slip ring 47 fixed to'that end of the drum which isoppoandone of'said brushes is connected with one pole of a generator G, or other sourceof current, and the other brush is connected with the other pole. provided with a switch 51 so that the circuit can be closed. andopened, whereby the magnet'is energized and deenergized in an obvious manner.

coil, which acts as an armature cooperating One of the leads is;

The end convolution 28 of the friction with the magnet, can either be'made from the same kind of steel fromwhich the friction 1 'coils are usually made, or it can be made of a soft dynamosteel similar to that which is preferably used in the construction of vthe magnet." In practice, the friction .coil 22 is bent up from a bar formed of aplurality of sections of varying'diameters, welded together end to end, and in the particular' form shown approximately the last two convolutions are intended to be constructed of soft dynamo steel. The weld between this section of the coil and theadjacentsection ls indicated by the dotted line 52 in Fig. 3.

Ofcoursethat face of the end convolually, net as is the case with the other. convolutions of the friction coil. This is an 'important feature, because as a result the tion 28 which. opposes the magnet 29, 32'

should be spaced from the magnet uniformly substantially throughout the periphery of said convolution andsaid magnet. The face of the magnet disposed-towardthe coil lies ina single vertical plane, and thereforethat face of .the end convolution 28 which-opposes the magnet lies substantially in a sin.

end convolution not only'acts'as an armature, but also fulfils its'function as a. art of the friction coil'in increasing the. rictional grip on the drum and augmenting the frictional engagement between the drum. and

the coil as a whole. 'It may be stated at thls point that the end convolution 28 of the rfictio'n coil is not the only convolution which is acted upon directly by the magnet,

gle vertical plane. i. In other words, in the particular form' shown, the magnet has a flat Working fface, and the end convolution of the coilhas a fiat cooperating face spaced equidistantlyfrom the magnet face at substantially allpoints. This end may be atcoil of-the special slia eshown in, Fig. 3. In other words, the width of the end convolution isso variedat different points as to preserve an equidistant spaging 'of the coil with respect. to the magnet substantially 1 throughout theperiphery .pf the coil and magnehalthough it is necessary to leave a small'gap,,53 atthe extremity ofthe, coil in order tenuow forthe contraction thereof.

. The friction coil 22 is preferably inclosed by suitable casing or shell 54 bolted to the contact with the non-magnetic ring or spacer 33, as shown in Fig. 1.' I p The operation of the clutch is substan tained by making. the end convolution of the driving plate 25, and extendingalmost into because as the magnet is substantially concentric with and of approximately the same diameter as the friction coil as awhole, 'the magnetic forceexerts an axial pull on sev eral oflthe coil convolutions which are ad-' jacent the magnet, and in this sense the armature consists, strictly speaking, ofmore than one convolution'of the coil. 'WWhe-n the switch 51 is opened, theend convolution 28 and any others which are under the direct influence of the magnetic pull, are immediatelyrelea'sed from their fixed position rela- 'tive to the magnet. The brass plate .133, or

its equivalent, interposed between the convolution 28 and the magnet, prevents these parts from, adhering to each other by residual magnetism when the current has been cut 011'. Of course, the clutch should be so designed, and such current provided that the brass plate, or its equivalent, will not'interfere in any appreciable'degree withthe .Ztially as follows; InFigQ-l, the switch 51.

' is open and the'cl'utchis in the oif tion, the wheel or pulley'20 being continuously rotated without-movement of the driven shaft 21. -'When it is desired to drive the shaftl21, the'switchis closed. It will be understood that at this'time the magnet is stationary, while the friction coll rotates freely aboutv the drum. In practice, the end convolution 28 of the friction coil will usually rotate in'light contact with the brass plate 33. As soon asthe magnet is energized,

/ however, the endconvolution 28 of the friction coil is strongly attracted toward the posimagnetic attraction of the armaturewhen the current is turned on, while on the other' hand, its neutralizing action will be suiii-.

cient toovercome theinconvenient effects of residual magnetism when .the current is turned off. As previously indicated, I do not limit myself to a plate interposed between'the armature, and magnet for this purpose, asother means for limiting the movement of the armature toward the mag:

net, or magnet toward the armature, andof preventing full metal to metal contact between these parts,.may be employed. 5 This insures a quickrelease of the friction coil when the current is turned-:ofi, so that it will magnet, and is tightly clamped againstthe brass plate 33,]which, in thecase illustrated, is -fixed relative to the magnet. Thus the free end portion of thefriction coil is locked or fixed relative to the stationary or slower moving magnet." As a consequence the tail 27 of the friction coil is cl-ragged back or re tarded relative to the main part ofthe friction coil, and .the'coil is thereby woundforx tightened on the drum 23;soas todrive the driven shaft. As soon as the tail :27 is fix'ed relative to the magnet by the energization of the latter, the coil begins to wind up from the free extremity 27, and the torsion thus' produced in the end convolution 28 is sufficient to eause it to grip the drum 23 frictionimmediately spring back out of engagement with the drum 23, and permit the drivenshaft to come to rest.

tact with-the magnet. On the other hand,

in those aspects of the invention which particularly concern the meansfor preventing the gripping together of the magnet and armature by residual magnetism, it is not always necessary to employ a friction coil in which the convolution at the free end acts as an armature. Various changes in the details of the construction maybe adopted-- when the magnet is energized, as: it does M when the magnet is denergized. In other words, it is not essential that the armature be in contact with the magnet at one time, andv that it be kept out of contact with the. magnet at another time, as in some prior constructions.

I do not claim broadly herein the combination of a driving member, a driven mem- 'ber, one of said members comprising a drum, a frict on coil attached to the other member and-embrac1ng said drum', a casing for the clutch, including an end plate, and a magnet structure. for locking the free end of the friction coil to said drum, including.

said end plate as, a part thereof, as claimed in my application Serial No. 861,825., Furthermore, I do not claimbroadly hereinthe combination of driving and driven mem- 'bers, one of said members comprising a drum, a friction coil attached to the other member and embracing sald drum, an end plate fixed to said drum, and electromagnetic means for. clamping said friction coil to said end plate, as claimed in my application Serial No.'84c,468. 1 lVhat I claim is: 1. A clutch having a driving part, a

driven part, a friction coil for coupling said parts together having a plurality of convolutions. and an electromagnet for operating said friction coil, located adjacent one of the coil convolutions 'and adapted to act thereon in a direction parallel to the axis of the fric tion coil'psubstantially as described.

Ina clutch, the combination of a drivin}: part, a driven part, a friction coil for coupling said parts together, having a plurality of convolutions, and an electromagnet for operating said friction coil adapted to act directly on one of said, convolution's throughout substantially the entire circumference or periphery of such convolution; substantially as described;

3. In a clutch, the driving part, a driven part, a helical friction coil for coupling said parts together,

- having one end attached to one of the clutch parts and provided at the opposite end with a free convolution, and an electromagnet for clamping the friction coil to the other clutch part, located. adjacent, the free end combination of a thereon in a direction parallel to the axis of the-friction coil substantially throughbut the circumference or periphery of the coil; substantially as described. p

4..Aclutch having a driving part, a. driven part, 'an electromagnet, and a friction coil carried by the driving part for coupling said partstogether, located concentrically with respect to said electromagnet, and having an end convolution serving as an armature therefor; substantially as described. I

5. A clutch having 'a driving part, a driven part, an electromagnethaving a ringlike coil, and a frictioncoil for coupling to-' gether the driving and driven parts, conconvolution and adapted to act directlycentric with the magnet coil and serving as the sole armature for the magnet;- substantially as described. l

6. A clutch having. a di'iving part, a

driven part, an electromagnet carried ,by

the driven part and having a ring-like coil,

driving part and. surrounding the driven part, said friction coil substantially concentric with said electromagnet, and serving as the sole armature therefor; substantia ll-y as described. l

7. A clutch havmg a driving part, a

driven part, an electromagnet, and a coil for h electromagnet, from said substantially coupling said parts together, having a con- T volution serving as an armature for 821d throughout the periphery of said convolu tion; substantially as described. 8. clutch having a driving part a driven part, an electromagnet having a working face in a plane substantially perpendicular to the. axis of rotation of said parts,.and a coil for coupling together said driving and driven parts, having an end convolution acting as an armature for said electromagnet', said end convolution pro-- vided with a working face in a plane parmagnet; substantially as described.-

9. A clutch having a driving part, a

drivenpart, an electromagnethaving a sub stantia-lly flat workingface located in'a allel to the working face of said electroing an integral end convolution acting as an armature for said electromagnet, said convolution provided with a flat working face opposing the working face of saidinagnet; substantlally as-described.

10. In a coilclutch, the combination of driving and driven members, one of said w members comprlslng a drum, a friction coil attached to the othermember and embracinterposed between said electromagnet and said armature member for .preventing metal --to metal contact of said partswhen the magnet is energized; substantially as described. I

ing s'aid drum, an end member fixed to said drum, a magnet carried by said end member,

.and means-for clamping the friction coil to said end member when the magnet is ener g'ized; substantially as described.

11. A clutch having a driving part, a driven part, an 'electromagnet comprising a metal plate or frame, and a magnet" coil carri'ed thereby, an armatu're member for said electromagnet, acoil operated by said armature member to couple together said driving and driven parts, and means preventing contact of said armature member with said electromagnet when the magnet "is energized; substantially as described.

12' A clutch having a driving part, a

driven part, an electromagnet comprising a metal plate or frame, and. a magnet coil carried" thereby, an armatureme'mber for said electromagnet, a friction coil operated by said armaturegmember to couple together said driving and driven parts, and means 13,.A clutch having a driving part a drivenpart, ani electromagnet," a friction coil forcoupling together said driving and driven parts, an armature for said electromagnet associated with said friction coil,

- and'means permanently spacing said armature member from said electromagnet to avoid the gripping together of said parts by residual magnetism; substantially as described.

14. A clutch having a driving part, a driven part, an electromagnet, a friction c'oil .for' coupling, together said driving and driven parts, an armature for said electromagnet associated with said friction coil,

and a member .of non-magnetic material interposed between said armature and said interposed between said end convolution and said magnet for preventing metal to metal contact of said armature and magnet when the latter is energized; substantially as de- 18. A clutch having a driving part, a' driven part, an electromagnet carried by the driven part, and comprising a-magnet plate.

and a ring'like magnet coil carried thereby, a friction coil for coupling together said driving and driven parts, carried by said driving part and surrounding the driven part, said friction coil being substantially concentric with saidmagnet coil and serving as an armature, and a non-magnetic plate preventing metal to metal contact of the friction coil and magnet when the latter is energized; substantially as described;

' 17. A clutch having a driving part, a-

driven part, an electromaget, a frictioncoil for coupling together said driving and driven parts, and an armature for said electromagnetjconnected with said friction coil, and permanently spaced from said electomagnet; substantially as described.

18. In a coil .clutch, the combination of driving and drivenmembers, one of said members comprising a drum, a friction coil attached to the other member and embracing said drum, an end'plate fixed to said drum, a magnet carried by the end plate, and

means for clamping the friction coil to the end plate when the magnet is energized;

' substantially as described.

.-19.'Ina coil clutch, the combination of driving and driven members, one of said memberscomprising a drum, a friction coil attached to the other member and embracing said drum, an end: plate fixed to the drum,

. and an annularelectromagnet 'carried by the endplate substantially in line with the friction coil; substantially: asdescribed 20. In. a coil clutch, the combination of driving and driven members, a friction coil attached at one end to one of said members and embracing the other member, and an annular electromagnetcarried by such other member in line with said friction coil and of substantially the same diameter assaidi coil; substantially as described.

21. In a clutch, a driving part, a driven part, an electromagnet, and a friction coil for coupling said driving anddriven parts together, having a plurality of convolutions,

one of said con olutions being opposed to the magnet to serve as an armature therefor,

. and at least one more convolution being under the direct influence of the magnet; sub? stantially as described.

22. A clutch having a driving part, a driven part, an electromagnet having a working face substantially perpendicular to the axis of rotation of said parts,' and a friction coil for coupling together said driv-.

ing and driven parts, provided with a squaredofi end convolution opposing said electromagnet, and in close proximity thereto; substantially as described.

23. In a coil clutch, the combination of two clutch members, a friction coil carried by one of said members and adapted to engage the other member, and an annular electromagnet fixed with respect to such other member and adapted to exert a mag netic pull on a plurality of the coil convo-,

lutions; substantially as described.

24. In a coil clutch, the combination of two main clutch members, a friction coil attached to one of said members and adapted to engage the other-member, said coil having a plurality of co'nvolutions, and

an annular magnet carried by such other .ad acent one end of the frict on c011 and substantially in line with said coil, said mag- 'net having a magnetic field including a plurality of the coil convolutions; substantially as described.

25. In a clutch, driving and driven mem bers, a friction coil for coupling said members together, and an electromagnet for operating said coil adapted to act on the latter in an axial direction by direct magnetic action on a plurality of the coil convolutions; substantially as described.

I 26, Ina coil clutch, the combination of a driving member, a driven member, one of said members comprising a drum, a friction coil surrounding the drum and attached to the other member, a plate secured to the end of the drum, andan annular electromagnet carried by the plate in linewith the friction coil and adapted to exert a magnetic pull on a plurality of the coil convolutions in a direction parallel to the axis of the drum.-

and coil; substantially as described.

27. In a coil clutch, the combination of two clutch members, one of said members comprisinga drum, a helical friction coil attached at one end to the other clutch memher and embracing said drum, and an electromagnet arranged to engage said friction coil with said drum by direct magnetic pull on a plurality of the coil convolutions in a. direction parallel to the axis of the drum;

substantially as described.

28. In a clutch, the combinationof a driving member, a driven member, one of said members comprising a drum, a friction coil attached to the other member and embracing said drum, an auxiliary clutch member carried by the drum, a second auxiliary clutch member at the free end of the friction coil, and an annular electromagnet sub- I stantially in line with said friction coil for interengaging the auxiliary clutch mem the axis,0f said coil; substantially as de-" scribed. v a a 30. In a coil clutch, thecombina-tion of a drivingmember, a driven member, one of s a1d members comprising a drum, a helical friction coil surrounding said drum and attached to the other member, and an annular magnetstructure located at the end of the friction coil and substantially in line with said friction coil for retarding the free end of the coil; substantially as described;

31. In a coil clutch, the combination of driving and driven members, one of said members comprising a drum, a friction coil surrounding the drum, means for securing one end of the friction coil to the other clutch member, an annular electromagnet carried by the clutclrmember surrounded by the friction coil, an annular member on the free end of the frictioncoil serving as an armature for said magnet, and-movable toward and away-from saidmagnet in a direction parallel with the axis of the fric 1 tion coil, and meansguiding said annular armature member for turning movement relative to the magnet; substantially as described. i v

32. In a' coil clutch, the combination of driving and driven members, one of which comprises a drum, a friction coil attached to the other member, and embracing said drum, a member fixed to said said drum in line with the free end of said friction coil,v

and a magnet carried by said member forclamping the friction coil to said lastnamed member; substantially'as described. 33. In a coil clutch, the combination of driving and driven members, a helical friction coil attached at one end to one of said members and embracing the other-member, a magnet-supporting member fixed to such other member adjacent the free end of said coil, and an electro-magnet carried by said magnet-supportingmember for coupling the driving and driven members by means of said friction coil; substantially as described;

3-1. In a coil clutch, the combination of driving and driven members,- a helical friction coil attached at one end to one of said members and embracing the other member a plate fixed to such other member and extending at right angles to'the axis of the friction coil adjacent the free end of said 0011, and an annular electro-magnet carried by said plate forretaidiiigtlie free end of the friction coil and thereby coupling the driving and driven members; substantially as described.

In witness whereof, I have hereunto set my hand on the 26th day of December, 1914.

' CARL F. SCHNUCK. Witnesses: OSWALD ULLRICI-I, ALBERT .B. C. SGHROEDER. 

